Commit | Line | Data |
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b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
e7d163f7 | 2 | #include <linux/zlib.h> |
4bedea94 CZ |
3 | |
4 | /* bits taken from ppc */ | |
5 | ||
6 | extern void *avail_ram, *end_avail; | |
7 | ||
8 | void exit (void) | |
9 | { | |
10 | for (;;); | |
11 | } | |
12 | ||
e7d163f7 | 13 | void *zalloc(unsigned size) |
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14 | { |
15 | void *p = avail_ram; | |
16 | ||
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17 | size = (size + 7) & -8; |
18 | avail_ram += size; | |
19 | if (avail_ram > end_avail) { | |
20 | //puts("oops... out of memory\n"); | |
21 | //pause(); | |
22 | exit (); | |
23 | } | |
24 | return p; | |
25 | } | |
26 | ||
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27 | #define HEAD_CRC 2 |
28 | #define EXTRA_FIELD 4 | |
29 | #define ORIG_NAME 8 | |
30 | #define COMMENT 0x10 | |
31 | #define RESERVED 0xe0 | |
32 | ||
33 | #define DEFLATED 8 | |
34 | ||
35 | void gunzip (void *dst, int dstlen, unsigned char *src, int *lenp) | |
36 | { | |
37 | z_stream s; | |
38 | int r, i, flags; | |
39 | ||
40 | /* skip header */ | |
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41 | i = 10; |
42 | flags = src[3]; | |
43 | if (src[2] != DEFLATED || (flags & RESERVED) != 0) { | |
44 | //puts("bad gzipped data\n"); | |
45 | exit(); | |
46 | } | |
47 | if ((flags & EXTRA_FIELD) != 0) | |
48 | i = 12 + src[10] + (src[11] << 8); | |
49 | if ((flags & ORIG_NAME) != 0) | |
50 | while (src[i++] != 0) | |
51 | ; | |
52 | if ((flags & COMMENT) != 0) | |
53 | while (src[i++] != 0) | |
54 | ; | |
55 | if ((flags & HEAD_CRC) != 0) | |
56 | i += 2; | |
57 | if (i >= *lenp) { | |
58 | //puts("gunzip: ran out of data in header\n"); | |
59 | exit(); | |
60 | } | |
61 | ||
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62 | s.workspace = zalloc(zlib_inflate_workspacesize()); |
63 | r = zlib_inflateInit2(&s, -MAX_WBITS); | |
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64 | if (r != Z_OK) { |
65 | //puts("inflateInit2 returned "); puthex(r); puts("\n"); | |
66 | exit(); | |
67 | } | |
68 | s.next_in = src + i; | |
69 | s.avail_in = *lenp - i; | |
70 | s.next_out = dst; | |
71 | s.avail_out = dstlen; | |
e7d163f7 | 72 | r = zlib_inflate(&s, Z_FINISH); |
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73 | if (r != Z_OK && r != Z_STREAM_END) { |
74 | //puts("inflate returned "); puthex(r); puts("\n"); | |
75 | exit(); | |
76 | } | |
77 | *lenp = s.next_out - (unsigned char *) dst; | |
e7d163f7 | 78 | zlib_inflateEnd(&s); |
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79 | } |
80 |